https://github.com/cran/pracma
Tip revision: c7b20449f057481c4a6908b43e23cbe9884eb57b authored by Hans W. Borchers on 14 January 2014, 00:00:00 UTC
version 1.6.1
version 1.6.1
Tip revision: c7b2044
roots.R
###
### ROOTS.R Matlab ROOTS Function
###
roots <- function(p) {
if (is.null(p) || length(p) == 0) return(matrix(0, nrow=0, ncol=0))
if ( !is.vector(p, mode="numeric"))
stop("Argument p must be a vector of real numbers.")
if (length(p) == 1) return(matrix(0, nrow=0, ncol=0))
# Find non-zero entries in p
inz <- which(p != 0)
nnz <- length(inz)
if (nnz == 0) return(c())
# Strip leading and trailing zeros, but remember the trailing zeros
q <- p[inz[1]:inz[nnz]]
r <- rep(0, length(p) - inz[nnz])
A <- compan(q)
return(c(r, eig(A)))
}